The present invention relates generally to a high intensity light irradiation apparatus using a dielectric barrier electrical discharge lamp for emitting high power of ultraviolet, more specifically to a simpler, lighter, and easy to assemble and replace support member for such high intensity light irradiation apparatus.
Dielectric barrier electrical discharge lamps find wide applications including curing ultraviolet curing resin in fabrication of semiconductor devices and liquid crystal display devices, purifying exhausted gases, and ultraviolet light sources for synthesizing chemical compounds.
A cross section view of a conventional high intensity light irradiation apparatus is illustrated in FIG. 3 and such conventional high intensity light irradiation apparatus comprises a ultraviolet transparent dielectric outer tube 11 and a dielectric inner tube 12 made from quartz glass or sapphire disposed concentrically with each other, a dielectric barrier electrical discharge lamp 1 having an electrical discharge space 14 filled with inert (or rare) gas such as argon, krypton, xenon, etc. Further comprising are a light transparent outer electrode 21 (e.g., mesh electrode, NESA coat, etc.) disposed on the surface of the dielectric outer tube 11, an inner electrode 22 disposed in a spiral manner on the surface of the dielectric inner tube 12 and an AC power source (not shown) for applying AC voltage between the outer electrode 21 and the inner electrode 22. High intensity ultraviolet is generated by plasma discharge in the electrical discharge space 14 by way of the layers of the dielectric tubes 11,12.
In such conventional high intensity light irradiation apparatus using dielectric barrier electrical discharge lamp 1 requires circulation of cooling water in the dielectric tube 12 for cooling the electrical discharge lamp 1. In addition to the cooling means, the electrical discharge lamp 1 requires a support member 9 for supporting the electrical discharge lamp 1 including the light transparent outer electrode 21 and the inner electrode 22.
Such support member 9 comprises an elongate rod member 91 longer than the electrical discharge lamp 1 to be supported, a pair of protrusions 92 raising from the both ends of the rod member 91 and each having a threaded hole 93 in parallel with the rod member 91, bushing members 94 screwed in the respective threaded holes 93, and sliding members 95 inserted into center holes of the bushing members 94 each provided with a flange 97 and an extending hole 96 for passing the cooling water therethrough.
For supporting the electrical discharge lamp 1 by the support member 9, the bushing members 94 are screwed from outside of the both protrusion members 94 to their half way and the sliding members 95 are slid into the center holes of respective bushing members 94. Both ends of the electrical discharge lamp 1 are clamped by the sliding members 95 by way of sealing gaskets 5 disposed in the respective flanges 97 of the both sliding members 95. Further screwing the bushing members 94 toward to each other, the sliding members 95 are pushed inwardly at their flanges 97, thereby reducing the distance between opposed sliding members 95 to apply desired clamping pressure onto the electrical discharge lamp 1. Finally, hoses for circulating the cooling water through the extending holes 96 are coupled to the inlet/outlet couplers 98 of the sliding members 95 and an AC power is connected between the outer electrode 21 and the inner electrode 22 of the electrical discharge lamp 1.
Now, the support member 9 for supporting the electrical discharge lamp 1 tends to become large and heavy because the support member 9 must provide sufficient mechanical strength so that the electrical discharge lamp 1 does not deform in operation.
When installing such electrical discharge lamp 1 supported by the large and heavy support member 9 onto an application machine, there are some restrictions in the design freedom of such application machine due to not only the size and weight but also replacement of the electrical discharge lamp 1 at the end of its lifetime. Accordingly, there is a strong need for providing a high intensity light irradiation apparatus using a simpler, lighter and easy to assemble and replace support member.